/**
 * Copyright &copy; 2017 <a href="https://gitee.com/hackempire/emsite-parent">emsite</a> All rights reserved.
 */
package com.empire.emsite.modules.sys.security;

import java.io.Serializable;
import java.util.Collection;
import java.util.List;

import javax.annotation.PostConstruct;

import org.apache.commons.lang3.StringUtils;
import org.apache.shiro.authc.AuthenticationException;
import org.apache.shiro.authc.AuthenticationInfo;
import org.apache.shiro.authc.AuthenticationToken;
import org.apache.shiro.authc.SimpleAuthenticationInfo;
import org.apache.shiro.authc.credential.HashedCredentialsMatcher;
import org.apache.shiro.authz.AuthorizationInfo;
import org.apache.shiro.authz.Permission;
import org.apache.shiro.authz.SimpleAuthorizationInfo;
import org.apache.shiro.realm.AuthorizingRealm;
import org.apache.shiro.session.Session;
import org.apache.shiro.subject.PrincipalCollection;
import org.apache.shiro.util.ByteSource;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Service;

import com.empire.emsite.common.config.GlobalConstants;
import com.empire.emsite.common.config.MainConfManager;
import com.empire.emsite.common.servlet.ValidateCodeServlet;
import com.empire.emsite.common.utils.Encodes;
import com.empire.emsite.common.utils.SpringContextHolder;
import com.empire.emsite.common.web.Servlets;
import com.empire.emsite.modules.sys.entity.Menu;
import com.empire.emsite.modules.sys.entity.Role;
import com.empire.emsite.modules.sys.entity.User;
import com.empire.emsite.modules.sys.service.SystemServiceUtils;
import com.empire.emsite.modules.sys.utils.LogUtils;
import com.empire.emsite.modules.sys.utils.UserUtils;
import com.empire.emsite.modules.sys.web.LoginController;

/**
 * 类SystemAuthorizingRealm.java的实现描述：系统安全认证实现类
 * 
 * @author arron 2017年10月30日 下午7:18:48
 */
@Service
//@DependsOn({"userDao","roleDao","menuDao"})
public class SystemAuthorizingRealm extends AuthorizingRealm {

    private Logger             logger = LoggerFactory.getLogger(getClass());

    private SystemServiceUtils systemServiceUtils;

    public SystemAuthorizingRealm() {
        this.setCachingEnabled(false);
    }

    /**
     * 认证回调函数, 登录时调用
     */
    @Override
    protected AuthenticationInfo doGetAuthenticationInfo(AuthenticationToken authcToken) {
        UsernamePasswordToken token = (UsernamePasswordToken) authcToken;

        int activeSessionSize = getSystemService().getSessionDao().getActiveSessions(false).size();
        if (logger.isDebugEnabled()) {
            logger.debug("login submit, active session size: {}, username: {}", activeSessionSize, token.getUsername());
        }

        // 校验登录验证码
        if (LoginController.isValidateCodeLogin(token.getUsername(), false, false)) {
            Session session = UserUtils.getSession();
            String code = (String) session.getAttribute(ValidateCodeServlet.VALIDATE_CODE);
            if (token.getCaptcha() == null || !token.getCaptcha().toUpperCase().equals(code)) {
                throw new AuthenticationException("msg:验证码错误, 请重试.");
            }
        }

        // 校验用户名密码
        User user = getSystemService().getUserByLoginName(token.getUsername());
        if (user != null) {
            if (GlobalConstants.YesNoEnum.NO.getValue().equals(user.getLoginFlag())) {
                throw new AuthenticationException("msg:该已帐号禁止登录.");
            }
            byte[] salt = Encodes.decodeHex(user.getPassword().substring(0, 16));
            return new SimpleAuthenticationInfo(new Principal(user, token.isMobileLogin()), user.getPassword()
                    .substring(16), ByteSource.Util.bytes(salt), getName());
        } else {
            return null;
        }
    }

    /**
     * 获取权限授权信息，如果缓存中存在，则直接从缓存中获取，否则就重新获取， 登录成功后调用
     */
    protected AuthorizationInfo getAuthorizationInfo(PrincipalCollection principals) {
        if (principals == null) {
            return null;
        }

        AuthorizationInfo info = null;

        info = (AuthorizationInfo) UserUtils.getCache(UserUtils.CACHE_AUTH_INFO);

        if (info == null) {
            info = doGetAuthorizationInfo(principals);
            if (info != null) {
                UserUtils.putCache(UserUtils.CACHE_AUTH_INFO, info);
            }
        }

        return info;
    }

    /**
     * 授权查询回调函数, 进行鉴权但缓存中无用户的授权信息时调用
     */
    @Override
    protected AuthorizationInfo doGetAuthorizationInfo(PrincipalCollection principals) {
        Principal principal = (Principal) getAvailablePrincipal(principals);
        // 获取当前已登录的用户
        if (!GlobalConstants.TrueFalseEnum.TRUE.getValue().equals(MainConfManager.getMultiAccountLogin())) {
            Collection<Session> sessions = getSystemService().getSessionDao().getActiveSessions(true, principal,
                    UserUtils.getSession());
            if (sessions.size() > 0) {
                // 如果是登录进来的，则踢出已在线用户
                if (UserUtils.getSubject().isAuthenticated()) {
                    for (Session session : sessions) {
                        getSystemService().getSessionDao().delete(session);
                    }
                }
                // 记住我进来的，并且当前用户已登录，则退出当前用户提示信息。
                else {
                    UserUtils.getSubject().logout();
                    throw new AuthenticationException("msg:账号已在其它地方登录，请重新登录。");
                }
            }
        }
        User user = getSystemService().getUserByLoginName(principal.getLoginName());
        if (user != null) {
            SimpleAuthorizationInfo info = new SimpleAuthorizationInfo();
            List<Menu> list = UserUtils.getMenuList();
            for (Menu menu : list) {
                if (StringUtils.isNotBlank(menu.getPermission())) {
                    // 添加基于Permission的权限信息
                    for (String permission : StringUtils.split(menu.getPermission(), ",")) {
                        info.addStringPermission(permission);
                    }
                }
            }
            // 添加用户权限
            info.addStringPermission("user");
            // 添加用户角色信息
            for (Role role : user.getRoleList()) {
                info.addRole(role.getEnname());
            }
            // 更新登录IP和时间
            getSystemService().updateUserLoginInfo(user);
            // 记录登录日志
            LogUtils.saveLog(Servlets.getRequest(), "系统登录");
            return info;
        } else {
            return null;
        }
    }

    @Override
    protected void checkPermission(Permission permission, AuthorizationInfo info) {
        authorizationValidate(permission);
        super.checkPermission(permission, info);
    }

    @Override
    protected boolean[] isPermitted(List<Permission> permissions, AuthorizationInfo info) {
        if (permissions != null && !permissions.isEmpty()) {
            for (Permission permission : permissions) {
                authorizationValidate(permission);
            }
        }
        return super.isPermitted(permissions, info);
    }

    @Override
    public boolean isPermitted(PrincipalCollection principals, Permission permission) {
        authorizationValidate(permission);
        return super.isPermitted(principals, permission);
    }

    @Override
    protected boolean isPermittedAll(Collection<Permission> permissions, AuthorizationInfo info) {
        if (permissions != null && !permissions.isEmpty()) {
            for (Permission permission : permissions) {
                authorizationValidate(permission);
            }
        }
        return super.isPermittedAll(permissions, info);
    }

    /**
     * 授权验证方法
     * 
     * @param permission
     */
    private void authorizationValidate(Permission permission) {
        // 模块授权预留接口
    }

    /**
     * 设定密码校验的Hash算法与迭代次数
     */
    @PostConstruct
    public void initCredentialsMatcher() {
        HashedCredentialsMatcher matcher = new HashedCredentialsMatcher(systemServiceUtils.HASH_ALGORITHM);
        matcher.setHashIterations(systemServiceUtils.HASH_INTERATIONS);
        setCredentialsMatcher(matcher);
    }

    //	/**
    //	 * 清空用户关联权限认证，待下次使用时重新加载
    //	 */
    //	public void clearCachedAuthorizationInfo(Principal principal) {
    //		SimplePrincipalCollection principals = new SimplePrincipalCollection(principal, getName());
    //		clearCachedAuthorizationInfo(principals);
    //	}

    /**
     * 清空所有关联认证
     * 
     * @Deprecated 不需要清空，授权缓存保存到session中
     */
    @Deprecated
    public void clearAllCachedAuthorizationInfo() {
        //		Cache<Object, AuthorizationInfo> cache = getAuthorizationCache();
        //		if (cache != null) {
        //			for (Object key : cache.keys()) {
        //				cache.remove(key);
        //			}
        //		}
    }

    /**
     * 获取系统业务对象
     */
    public SystemServiceUtils getSystemService() {
        if (systemServiceUtils == null) {
            systemServiceUtils = SpringContextHolder.getBean(SystemServiceUtils.class);
        }
        return systemServiceUtils;
    }

    /**
     * 授权用户信息
     */
    public static class Principal implements Serializable {

        private static final long serialVersionUID = 1L;

        private String            id;                   // 编号
        private String            loginName;            // 登录名
        private String            name;                 // 姓名
        private boolean           mobileLogin;          // 是否手机登录

        //		private Map<String, Object> cacheMap;

        public Principal(User user, boolean mobileLogin) {
            this.id = user.getId();
            this.loginName = user.getLoginName();
            this.name = user.getName();
            this.mobileLogin = mobileLogin;
        }

        public String getId() {
            return id;
        }

        public String getLoginName() {
            return loginName;
        }

        public String getName() {
            return name;
        }

        public boolean isMobileLogin() {
            return mobileLogin;
        }

        //		@JsonIgnore
        //		public Map<String, Object> getCacheMap() {
        //			if (cacheMap==null){
        //				cacheMap = new HashMap<String, Object>();
        //			}
        //			return cacheMap;
        //		}

        /**
         * 获取SESSIONID
         */
        public String getSessionid() {
            try {
                return (String) UserUtils.getSession().getId();
            } catch (Exception e) {
                return "";
            }
        }

        @Override
        public String toString() {
            return id;
        }

    }
}
